I am using a custom toolbar. I need to add back button to it. Now I am using this code to add the back button.
Toolbar toolbar = (Toolbar) getActivity().findViewById(R.id.toolbar);
toolbar.setBackgroundColor(getResources().getColor(R.color.white));
toolbar.setNavigationIcon(getResources().getDrawable(R.drawable.back_arrow));
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
onBackPressed();
}
});
This works fine. I can see the back button added. But consider the case where I am in Fragment1 which has no back button. Now I move to Fragment2 and I add in Back Button. From Fragment 2 I open Fragment 3 and I add the back button again.
Now when I press back button from fragment3 to go back to fragment2 i have to check the Fragment Stack to see whether the back button is required in fragment 2 or not.
Is there any other way to handle back button automatically as we push fragments to stack?
Just add two new line of code. Something like this
Toolbar toolbar = (Toolbar) getActivity().findViewById(R.id.toolbar);
toolbar.setBackgroundColor(getResources().getColor(R.color.white));
toolbar.setNavigationIcon(getResources().getDrawable(R.drawable.back_arrow));
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
onBackPressed();
}
});
This assumes you are using an AppCompatActivity
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
toolbar = (Toolbar) findViewById(R.id.tool_bar); // Attaching the layout to the toolbar object
setSupportActionBar(toolbar);
// enabling action bar app icon and behaving it as toggle button
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setHomeButtonEnabled(true);
}
Then in the onOptionsItemSelected you can override the home button as follows:
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
else if(id == android.R.id.home){
Intent i= new Intent(this, MainActivity.class);
i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(i);
finish();
return true;
}
return super.onOptionsItemSelected(item);
}
You can handle back icon very easily. If all of your fragment are in single Activity I really recommend to handle this with following way :
first crate a abstract BaseFragment class which implement FragmentManager .OnBackStackChangedListener then put following method inside that :
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mainActivity = (MainActivity) getActivity();
getFragmentManager().addOnBackStackChangedListener(this);
shouldDisplayHomeUp();
}
#Override
public void onBackStackChanged() {
shouldDisplayHomeUp();
}
public boolean shouldDisplayHomeUp() {
//Enable Up button only if there are entries in the back stack
boolean canBack = false;
try {
canBack = getFragmentManager().getBackStackEntryCount() > 0;
} catch (Exception ex) {
// Log.e(getClass().getCanonicalName(), ex.getMessage());getMessage
}
if (canBack) {
mainActivity.drawerDisable();
} else {
mainActivity.drawerEnable();
}
return canBack;
}
By this way disableDrawer & enableDrawer function handle your Icon and OnBackPressed method handle your BackStack Now in your activity when you press back-icon display if needed. your onBackPressed should be something like this :
int backStackCount = getSupportFragmentManager().getBackStackEntryCount();
if (backStackCount == 0) {
//nothing exist in backStack OS handle it
super.onBackPressed();
} else {
getSupportFragmentManager().popBackStack();
}
See full implementation here.
use Method in Class your Activity
private void setupToolbar(){
Toolbar toolbar=(Toolbar)findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
ActionBar actionBar=getSupportActionBar();
actionBar.setDisplayHomeAsUpEnabled(true);
actionBar.setDisplayShowHomeEnabled(true);
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
finish();
}
});
}
It's works on back pressed function to toolbar
private setUpToolBar() {
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setDisplayShowHomeEnabled(true);
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
onBackPressed();
}
});
}
i have Main activity and Four fragments.
In MainActivity i write this code
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
onBackPressed();
}
});
this is working fine and if you have fragments then create a onBackPressed() method
#Override
public void onBackPressed() {
int position = mViewPager.getCurrentItem();
if(position == 2) { // go back to search / result tab from info detail tab
mViewPager.setCurrentItem(2);
} else if(position == 0) { // switch from result to search tab or go back to home tab
SectionsPagerAdapter sectionsPagerAdapter = (SectionsPagerAdapter) mViewPager.getAdapter();
Fragment fragment = sectionsPagerAdapter.getItem(position);
if(fragment instanceof ResultFragment) {
Bundle bundle = ((ResultFragment) fragment).getArguments();
if(bundle != null) {
sectionsPagerAdapter.replaceFragment(SearchFragment.newInstance(bundle.getString(GlobalInfo.TAG_ID), bundle.getString(GlobalInfo.PART_NO), bundle.getString(GlobalInfo.SERIAL_NO), bundle.getString(GlobalInfo.PART_NAME)), getString(R.string.search), 0);
}
} else {
mViewPager.setCurrentItem(1);
}
}
else if(position == 3){
SectionsPagerAdapter sectionsPagerAdapter = (SectionsPagerAdapter) mViewPager.getAdapter();
Fragment fragment = new ToolMgtFragment();
sectionsPagerAdapter.replaceFragment(fragment,"Tool Mgt", 3);
}
else {
super.onBackPressed();
}
}
Related
I have two fragments FragmentHome and FragmentAbout, I have added NavigationDrawer to app when I click Home it opens FragmentHome and About opens FragmentAbout, when I open FragmentAbout I am also adding it to backstack. This is working fine.
Now the problem is when I click on About and press back button it goes to the FragmentHome but the NavigationDrawer still shows the About as selected item, I want to change this selected item to Home when I press back button from FragmentAbout
Home Activity:
public class ActivityHome extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener {
Toolbar toolbar;
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
// Toolbar
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
// Drawer layout
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.nav_drawer_layout);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this, drawer, toolbar, R.string.nav_drawer_open, R.string.nav_drawer_close);
assert drawer != null;
drawer.setDrawerListener(toggle);
toggle.syncState();
// Navigation view
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
assert navigationView != null;
navigationView.setNavigationItemSelectedListener(this);
// Open first menu item
navigationView.getMenu().performIdentifierAction(R.id.nav_home, 0);
// Set first item checked
navigationView.setCheckedItem(R.id.nav_home);
}
#SuppressWarnings("StatementWithEmptyBody")
#Override
public boolean onNavigationItemSelected(MenuItem item) {
final MenuItem menuItem = item;
// Check if menu item is selected
if (item.isChecked())
item.setChecked(false);
else
item.setChecked(true);
// Handle navigation view item clicks here.
int id = item.getItemId();
if (id == R.id.nav_home) {
// Open home fragment
getSupportFragmentManager().beginTransaction()
.replace(R.id.frame_layout, new FragmentHome())
.commit();
} else if (id == R.id.nav_about) {
toolbar.setTitle("About");
// Open home fragment
getSupportFragmentManager().beginTransaction()
.replace(R.id.frame_layout, new FragmentAbout())
.addToBackStack(null)
.commit();
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.nav_drawer_layout);
assert drawer != null;
drawer.closeDrawer(GravityCompat.START);
return true;
}
#Override
public void onBackPressed() {
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.nav_drawer_layout);
assert drawer != null;
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
} else {
super.onBackPressed();
}
}}
FragmentHome
public class FragmentHome extends Fragment {
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_home, container, false);
}
#Override
public void onResume() {
super.onResume();
((AppCompatActivity)getActivity()).getSupportActionBar().setTitle(R.string.fragment_home_title);
}
}
FragmentAbout code is same as FragmentHome just layout change.
I have searched a lot on stackoverflow but didn't find any solution yet, so if someone know how to do this please tell me.
There is a OnBackStackChangedListener that you can use for this. Tried it and it works great.
public Fragment getCurrentFragment() {
return this.getSupportFragmentManager().findFragmentById(R.id.fragment_container);
}
#Override
protected void onCreate(Bundle savedInstanceState) {
...
this.getSupportFragmentManager().addOnBackStackChangedListener(
new FragmentManager.OnBackStackChangedListener() {
public void onBackStackChanged() {
Fragment current = getCurrentFragment();
if (current instanceof MyFragmentA) {
navigationView.setCheckedItem(R.id.nav_myfragA);
} else {
navigationView.setCheckedItem(R.id.nav_myfragB);
}
}
});
...
}
This might not be a good solution, but at least it is acceptable for me. You need to store fragment's position inside stack variable (ex: List) whenever a fragment menu is clicked from nav drawer. Then override onBackPressed to remove the last value from stack, and set drawer position to the current last value of stack. Here's the example:
private List<Integer> itemPositionStacks = new ArrayList<>();
protected void onCreate(#Nullable Bundle savedInstanceState) {
itemPositionStacks.add(currentSelectedPosition);
}
public void onNavigationViewItemSelected(int itemId) {
Fragment fr = null;
switch (itemId) {
case 0:
fr = new aFragment();
break;
case 1:
fr = new bFragment();
break;
}
getSupportFragmentManager().beginTransaction()
.replace(R.id.container, fr)
.addToBackStack(null)
.commit();
Drawer.getInstance().setDrawerChecked(itemId);
itemPositionStacks.add(itemId);
}
public void onBackPressed() {
if(itemPositionStacks.size() > 1) {
itemPositionStacks.remove(itemPositionStacks.size() - 1);
Drawer.getInstance().setDrawerChecked(itemIdStacks.get(itemIdStacks.size() - 1));
}
super.onBackPressed();
}
In your onBackPressed() function ..
you must choose which item to be selected by using
drawer.setCheckedItem(R.id.nav_home);
and remove the selection of the another item
drawer.getMenu().findItem(R.id.nav_about).setChecked(false);
I have 2 activites:
- LoginActivity: it will handle the login stuff later
- MainActivity: the main app, all of the functions will be provided on fragments.
I want to properly use the back stack, but I can't.
What I want (but can't) achieve:
App starts with Login screen. I login (right now press the Start button), after that the main screen appears and the first fragment loads.
Now if I press the back button, the app closes, and that's how it should work, it must not go back to the login screen with a simple back button press.
But now if I click logout (and the Login screen appears), and I press the back button, the app takes me back to the main screen, what is really not ok. If I log out, from the login screen the back button should close the app.
And another problem, regarding also backstack, and fragments:
I have 3 fragments: first, second and third. If I open them after each other (within the main activity of course), and I press the back button, I want it to take me back to the previously opened fragment, or if there's no previous, close the app.
Now it makes it, opens the previous fragment, but at the same time it closes the complete app. (I can see that they are happening right after each other)
What's missing? What should be modified to achieve this (normal) behavior?
Thanks!
My code:
MainActivity:
public class MainActivity extends AppCompatActivity
implements NavigationView.OnNavigationItemSelectedListener {
public static final String SP_DATA = "SP_DATA";
public static final String FB_LOGIN_STATUS = "FB_LOGIN_STATUS";
public static final String FLRT = "FLRT";
public SharedPreferences sharedPreferences;
#Override
protected void onCreate(Bundle savedInstanceState) {
sharedPreferences = getSharedPreferences(SP_DATA, MODE_PRIVATE);
boolean bAlreadyLoggedIn = sharedPreferences.getBoolean(FB_LOGIN_STATUS, false);
if (bAlreadyLoggedIn) {
Log.d(FLRT, "Already logged in");
}
else {
Log.d(FLRT, "Not logged in");
Intent intent = new Intent(MainActivity.this, LoginActivity.class);
startActivity(intent);
}
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
showFragment(new FirstFragment(),"FirstFragment");
Button btnLogout = (Button) findViewById(R.id.btnLogout);
btnLogout.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
logout();
showActivity(MainActivity.this, LoginActivity.class);
}
});
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
drawer.setDrawerListener(toggle);
toggle.syncState();
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);
}
private void showActivity(Context context_fromActivity, Class<?> class_toActivty){
Intent intent = new Intent(context_fromActivity, class_toActivty);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);
}
private void logout() {
Log.d(FLRT, "Logging out...");
sharedPreferences = getSharedPreferences(SP_DATA, MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putBoolean(FB_LOGIN_STATUS, false);
editor.commit();
}
#Override
public void onBackPressed() {
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
} else {
super.onBackPressed();
}
if (getFragmentManager().getBackStackEntryCount() > 0 ){
getFragmentManager().popBackStack();
} else {
super.onBackPressed();
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
#SuppressWarnings("StatementWithEmptyBody")
#Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
int id = item.getItemId();
if (id == R.id.nav_first_layout) {
showFragment(new FirstFragment(), "FirstFragment");
}
else if (id == R.id.nav_second_layout) {
showFragment(new SecondFragment(), "SecondFragment");
}
else if (id == R.id.nav_third_layout) {
showFragment(new ThirdFragment(), "ThirdFragment");
}
else if (id == R.id.nav_share) {
}
else if (id == R.id.nav_send) {
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
return true;
}
private void showFragment(Fragment fragment, String sFragmentTAG) {
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
if (fragmentManager.findFragmentByTag(sFragmentTAG) != null) {
Log.d(FLRT, "Fragment found, using existing one: " + sFragmentTAG);
fragment = fragmentManager.findFragmentByTag(sFragmentTAG);
}
fragmentTransaction.replace(R.id.fragmentContainer, fragment, sFragmentTAG);
fragmentTransaction.addToBackStack(null);
fragmentTransaction.commit();
}
}
LoginActivity:
public class LoginActivity extends AppCompatActivity {
public static final String SP_DATA = "SP_DATA";
public static final String FB_LOGIN_STATUS = "FB_LOGIN_STATUS";
public static final String FLRT = "FLRT";
public SharedPreferences sharedPreferences;
private Button btn_start;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
btn_start = (Button) findViewById(R.id.btn_start);
btn_start.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
login();
showActivity(LoginActivity.this, MainActivity.class);;
}
});
}
private void showActivity(Context context_fromActivity, Class<?> class_toActivty){
Intent intent = new Intent(context_fromActivity, class_toActivty);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);
}
private void login() {
Log.d(FLRT, "Logging in...");
sharedPreferences = getSharedPreferences(SP_DATA, MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putBoolean(FB_LOGIN_STATUS, true);
editor.commit();
}
}
About switching between Activities.
One important thing.
In showActivity() use finish() to kill current Activity when going to another. If it doesn't help - see below.
Try to use also FLAG_ACTIVITY_NEW_TASK with your current flag, because FLAG_ACTIVITY_CLEAR_TOP will close only Activities in task above current Activity, but not below.
So, it would be this: intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_CLEAR_TASK);
Another option is to use: FLAG_ACTIVITY_CLEAR_TASK only - new Activity will clear the task and become root in it.
If both won't help - use android:launchMode = "singleInstance" in Manifest for each Actitivy.
About Fragments - I see a little mistake in your code: it calls super.onBackPressed(); before popping Fragment from BackStack
I would change like this:
#Override
public void onBackPressed() {
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
} else if (getFragmentManager().getBackStackEntryCount() > 0 ){
getFragmentManager().popBackStack();
} else {
super.onBackPressed();
}
}
!! Also you should test this line: getFragmentManager().getBackStackEntryCount() > 0 with 0 and 1 in condition (because in current implementation in my project FragmentContainer is considering as first, zero value in a BackStack). Just test 0 and 1 to see which works.
Thanks.
PS. Few more tips.
You can declare FragmentManager fragmentManager in your Activity in order to create it one time only in onCreate(). It would be better than get it each time.
Consider change this:
if (id == R.id.nav_first_layout) {
showFragment(new FirstFragment(), "FirstFragment");
}
else if (id == R.id.nav_second_layout) {
showFragment(new SecondFragment(), "SecondFragment");
}
else if (id == R.id.nav_third_layout) {
showFragment(new ThirdFragment(), "ThirdFragment");
}
else if (id == R.id.nav_share) {
}
else if (id == R.id.nav_send) {
}
To:
switch (item.getItemId()) {
case R.id.nav_first_layout:
showFragment(new FirstFragment(), "FirstFragment");
break;
case ...
}
and so on. The code would be more pretty :)
Currently Used Google Navigation Drawer, having some problem when user backpress.
When user backpress, they didn't update menu Item
Example When I click the App. The sequence are A>B>C>B>C ,if I backpress I wanted to be C>B>A. How should I code this way out ?
My code
public class MainActivity extends AppCompatActivity {
private String appTitle;
private Toolbar toolbar;
private NavigationView navigationView;
private DrawerLayout drawerLayout;
private TextView toolbarTitle;
private Fragment fragment;
private FragmentManager fragmentManager;
private Title title;
private MenuItem menuItem2;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Actionbar
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
toolbarTitle = (TextView) toolbar.findViewById(R.id.toolbar_title);
toolbarTitle.setTextColor(Color.parseColor("#FFFFFF"));
setTitle("");
fragmentManager = getSupportFragmentManager();
fragment= new HomeFragment();
title = new Title(getApplicationContext());
fragmentManager.beginTransaction().replace(R.id.content_frame,fragment , title.getStrHome()).commit();
navigationView = (NavigationView) findViewById(R.id.navigation_view);
navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(MenuItem menuItem) {
menuItem2 = menuItem;
menuItem.setChecked(true);
drawerLayout.closeDrawers();
if (menuItem.getItemId() == R.id.nav_home) {
fragment = new HomeFragment();
appTitle = title.getStrHome();
} else if ((menuItem.getItemId() == R.id.nav_direction)) {
fragment = new DirectionFragment();
appTitle = title.getStrDirection();
} else if ((menuItem.getItemId() == R.id.nav_more)) {
fragment = new MoreFragment();
appTitle = title.getStrMore();
} else if((menuItem.getItemId()==R.id.nav_directory)){
fragment = new DirectoryFragment();
appTitle = title.getStrDirectory();
}
else {
Toast.makeText(getApplicationContext(), "Error", Toast.LENGTH_SHORT).show();
}
replaceFragment(fragment,appTitle);
return true;
}
});
drawerLayout = (DrawerLayout) findViewById(R.id.drawer);
ActionBarDrawerToggle actionBarDrawerToggle =
new ActionBarDrawerToggle
(this,drawerLayout,toolbar,R.string.drawer_open,R.string.drawer_close){
#Override
public void onDrawerClosed(View drawerView) {
super.onDrawerClosed(drawerView);
}
#Override
public void onDrawerOpened(View drawerView) {
super.onDrawerOpened(drawerView);
}
};
drawerLayout.setDrawerListener(actionBarDrawerToggle);
actionBarDrawerToggle.syncState();
}
public void onBackPressed() {
if(drawerLayout.isDrawerOpen(GravityCompat.START)){
drawerLayout.closeDrawer(GravityCompat.START);
}
else {
if (fragmentManager.getBackStackEntryCount() > 0 ){
fragmentManager.popBackStack();
toolbarTitle.setText(appTitle);
menuItem2.setChecked(true);
} else {
finish();
}
}
}
public void replaceFragment(Fragment fragment, String tag){
toolbarTitle.setText(tag);
FragmentTransaction ft = fragmentManager.beginTransaction().replace(R.id.content_frame, fragment, tag);
ft.addToBackStack(tag);
ft.commit();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
As stated on the official page on Android tasks and back stack you can see how you can accomplish your desired behaviour using the FLAG_ACTIVITY_CLEAR_TOP in your Intent flags. This picture demonstrates it very well.
Your regular back button proceeds as:
When you specify this flag, you get a behavior like you need
Edit:
The official documentation states:
FLAG_ACTIVITY_CLEAR_TOP
If the activity being started is already running in the current task, then instead of launching a new instance of that activity, all of the
other activities on top of it are destroyed
This means, there will be no duplicates of your different Activities, and you will have a clean Back Stack.
In your example A>B>C>B>C would not be possible. Instead it would be A>B>C, since B and C already exist in the stack, they will not be added, but replaced instead.
Study the Android Activity Launch Mode.
here is the clear Explanation available.
Just take a look.
I'm using the new toolbar from the Appcompat V7 library and I'm making an application with navigation drawer and with fragments.
In some fragments I don't want to show the hamburger icon but the arrow instead... That is fine I did this in this way:
mDrawerToggle.setDrawerIndicatorEnabled(false);
mDrawerToggle.syncState();
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setHomeButtonEnabled(true);
getSupportActionBar().setDisplayShowHomeEnabled(true);
getSupportActionBar().setHomeAsUpIndicator(R.drawable.abc_ic_ab_back_mtrl_am_alpha);
My question is that: How or where i need to set up the home button lisener or what i need to listen for the "back" button ?
I want to call the main backpressed method and to set back the navigation drawer icon with the hamburger icon..
Add this method in onCreate():
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
Then override the onOptionItemSelected() as below:
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
onBackPressed();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
You can do it like this:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
toolbar = (Toolbar)findViewById(R.id.toolbar);
if (toolbar != null) {
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
}
setUpNavigationDrawer();
getFragmentManager().addOnBackStackChangedListener(backStackListener); // listen to the backstack of the fragment manager
}
Define the onBackSTackChangedListener:
private FragmentManager.OnBackStackChangedListener backStackListener = new FragmentManager.OnBackStackChangedListener() {
#Override
public void onBackStackChanged() {
setNavIcon();
};
}
Set the icon according to your fragment's backstack:
protected void setNavIcon() {
int backStackEntryCount = getFragmentManager().getBackStackEntryCount();
drawerToggle.setDrawerIndicatorEnabled(backStackEntryCount == 0);
}
Detect when the drawer icon is pressed:
public boolean onOptionsItemSelected(MenuItem item) {
if (drawerToggle.isDrawerIndicatorEnabled() && drawerToggle.onOptionsItemSelected(item)) {
return true;
}
switch (item.getItemId()) {
case x:
return true;
default:
return false;
}
}
And handle the up button:
public boolean onSupportNavigateUp() {
onBackPressed();
return true;
}
This works for me. Good luck.
Not sure if this works in OP's case, but in many cases this is probably the simplest option to implement Back button with the AppCompat Toolbar.
Skip all the setHomeButtonEnabled, setDisplayHomeAsUpEnabled and onOptionsItemSelected stuff, and related issues.
Instead, when initialising the Toolbar, simply set 1) navigation icon and 2) navigation OnClickListener for it:
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
if (enableBackNavigation) {
toolbar.setNavigationIcon(R.drawable.ic_back);
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
onBackPressed();
}
});
}
1- Create Toolbar layout;
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:local="http://schemas.android.com/apk/res-auto"
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/dark_blue"
android:minHeight="?attr/actionBarSize"
local:popupTheme="#style/ThemeOverlay.AppCompat.Light"
local:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar" />
2- Include this in your layout at the place where you want the toolbar to be.
3- Paste the following code in your activity.(extends ActionBarActivity)
private Toolbar mToolbar;
//For Toolbar (Action bar) start
mToolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(mToolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setDisplayShowHomeEnabled(true);
mToolbar.setNavigationIcon(R.drawable.ic_back_arrow);
mToolbar.setNavigationOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
onBackPressed();
}
});
getSupportActionBar().setTitle("Event Details");
//For Toolbar (Action bar) end
4- change the back click icon to whatever you want.
activate the back button:
getActionBar().setDisplayHomeAsUpEnabled(enable);
and listen for clicks in onBackPressed()
Obviously your activity must extend ActionBarActivity
Simply you can set Navigation icon and make sure you are setting setNavigationOnClickListener() after setting setSupportActionBar(toolbar)
toolbar.setNavigationIcon(getResources().getDrawable(R.drawable.ic_arrow_back));
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
onBackPressed();
}
});
in manifest add these lines under the activity you want the back arrow working
android:parentActivityName="Your parent activity name"
Add setDisplayHomeAsUpEnabled(true)
Toolbar toolbar = findViewById(R.id.toolbar);
ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
actionBar.setDisplayHomeAsUpEnabled(true);
}
Handle the back button
public boolean onSupportNavigateUp() {
onBackPressed();
return true;
}
I've implemented the newest appcompat library and using the Toolbar as action bar. But the problem is I cannot catch the home button / hamburger icon click event. I've tried and looked everything but doesn't seem to find a similar problem.
This is my Activity class :
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
// Set up the drawer.
navDrawerFragment =
(NavigationDrawerFragment) getSupportFragmentManager()
.findFragmentById(R.id.navigation_drawer);
navDrawerFragment.setUp(
R.id.navigation_drawer,
(DrawerLayout) findViewById(R.id.drawer_layout),
toolbar);
}
And this is my NavigationDrawerFragment class :
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (savedInstanceState != null) {
currentSelectedPosition = savedInstanceState.getInt(
STATE_SELECTED_POSITION);
fromSavedInstanceState = true;
}
// Select either the default item (0) or the last selected item.
selectItem(currentSelectedPosition);
}
#Override
public void onActivityCreated (Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
// Indicate that this fragment would like
// to influence the set of actions in the action bar.
setHasOptionsMenu(true);
}
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
drawerListView = (ListView) inflater.inflate(
R.layout.fragment_navigation_drawer, container, false);
drawerListView.setOnItemClickListener(
new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent,
View view, int position, long id) {
selectItem(position);
}
});
//mDrawerListView.setAdapter();
//mDrawerListView.setItemChecked(mCurrentSelectedPosition, true);
return drawerListView;
}
public void setUp(int fragmentId, DrawerLayout drawerLayout, Toolbar toolbar) {
fragmentContainerView = getActivity().findViewById(fragmentId);
this.drawerLayout = drawerLayout;
// set a custom shadow that overlays the main
// content when the drawer opens
drawerLayout.setDrawerShadow(
R.drawable.drawer_shadow, GravityCompat.START);
// set up the drawer's list view
// with items and click listener
ActionBar actionBar = getActionBar();
actionBar.setDisplayHomeAsUpEnabled(true);
actionBar.setHomeButtonEnabled(true);
// ActionBarDrawerToggle ties together the the proper interactions
// between the navigation drawer and the action bar app icon.
drawerToggle = new ActionBarDrawerToggle(
getActivity(),
drawerLayout,
toolbar,
R.string.navigation_drawer_open,
R.string.navigation_drawer_close) {
public void onDrawerClosed(View view) {
super.onDrawerClosed(view);
}
public void onDrawerOpened(View drawerView) {
super.onDrawerOpened(drawerView);
}
};
// If the user hasn't 'learned' about the drawer,
// open it to introduce them to the drawer,
// per the navigation drawer design guidelines.
if (!userLearnedDrawer && !fromSavedInstanceState) {
drawerLayout.openDrawer(fragmentContainerView);
}
// Defer code dependent on restoration of previous instance state.
drawerLayout.post(new Runnable() {
#Override
public void run() {
drawerToggle.syncState();
}
});
drawerLayout.setDrawerListener(drawerToggle);
}
#Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putInt(STATE_SELECTED_POSITION, currentSelectedPosition);
}
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
// Forward the new configuration the drawer toggle component.
drawerToggle.onConfigurationChanged(newConfig);
}
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
super.onCreateOptionsMenu(menu, inflater);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
Log.d("cek", "item selected");
if (drawerToggle.onOptionsItemSelected(item)) {
Log.d("cek", "home selected");
return true;
}
return super.onOptionsItemSelected(item);
}
when I clicked a menu item, the log "item selected" gets called. But when I click on the home button, it opens navigation drawer but the log "home selected" never get called. I've set onOptionsItemSelected method inside my Activity as well, but it still doesn't get called.
If you want to know when home is clicked is an AppCompatActivity then you should try it like this:
First tell Android you want to use your Toolbar as your ActionBar:
setSupportActionBar(toolbar);
Then set Home to be displayed via setDisplayShowHomeEnabled like this:
getSupportActionBar().setDisplayShowHomeEnabled(true);
Finally listen for click events on android.R.id.home like usual:
#Override
public boolean onOptionsItemSelected(MenuItem menuItem) {
if (menuItem.getItemId() == android.R.id.home) {
Timber.d("Home pressed");
}
return super.onOptionsItemSelected(menuItem);
}
If you want to know when the navigation button is clicked on a Toolbar in a class other than AppCompatActivity you can use these methods to set a navigation icon and listen for click events on it. The navigation icon will appear on the left side of your Toolbar where the the "home" button used to be.
toolbar.setNavigationIcon(getResources().getDrawable(R.drawable.ic_nav_back));
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Log.d("cek", "home selected");
}
});
If you want to know when the hamburger is clicked and when the drawer opens, you're already listening for these events via onDrawerOpened and onDrawerClosed so you'll want to see if those callbacks fit your requirements.
mActionBarDrawerToggle = mNavigationDrawerFragment.getActionBarDrawerToggle();
mActionBarDrawerToggle.setToolbarNavigationClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// event when click home button
}
});
in mycase this code work perfect
This is how I do it to return to the right fragment otherwise if you have several fragments on the same level it would return to the first one if you don´t override the toolbar back button behavior.
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
finish();
}
});
I think the correct solution with support library 21 is the following
// action_bar is def resource of appcompat;
// if you have not provided your own toolbar I mean
Toolbar toolbar = (Toolbar) findViewById(R.id.action_bar);
if (toolbar != null) {
// change home icon if you wish
toolbar.setLogo(this.getResValues().homeIconDrawable());
toolbar.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
//catch here title and home icon click
}
});
}
I have handled back and Home button in Navigation Drawer like
public class HomeActivity extends AppCompatActivity
implements NavigationView.OnNavigationItemSelectedListener {
private ActionBarDrawerToggle drawerToggle;
private DrawerLayout drawerLayout;
NavigationView navigationView;
private Context context;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
resetActionBar();
navigationView = (NavigationView) findViewById(R.id.navigation_view);
navigationView.setNavigationItemSelectedListener(this);
//showing first fragment on Start
getSupportFragmentManager().beginTransaction().setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN).replace(R.id.content_fragment, new FirstFragment()).commit();
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
//listener for home
if(id==android.R.id.home)
{
if (getSupportFragmentManager().getBackStackEntryCount() > 0)
onBackPressed();
else
drawerLayout.openDrawer(navigationView);
return true;
}
return super.onOptionsItemSelected(item);
}
#Override
public void onBackPressed() {
if (drawerLayout.isDrawerOpen(GravityCompat.START))
drawerLayout.closeDrawer(GravityCompat.START);
else
super.onBackPressed();
}
#Override
public boolean onNavigationItemSelected(MenuItem item) {
// Begin the transaction
Fragment fragment = null;
// Handle navigation view item clicks here.
int id = item.getItemId();
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
if (id == R.id.nav_companies_list) {
fragment = new FirstFragment();
// Handle the action
}
// Begin the transaction
if(fragment!=null){
if(item.isChecked()){
if(getSupportFragmentManager().getBackStackEntryCount()==0){
drawer.closeDrawers();
}else{
removeAllFragments();
getSupportFragmentManager().beginTransaction().setTransition(FragmentTransaction.TRANSIT_FRAGMENT_CLOSE).replace(R.id.WikiCompany, fragment).commit();
drawer.closeDrawer(GravityCompat.START);
}
}else{
removeAllFragments();
getSupportFragmentManager().beginTransaction().setTransition(FragmentTransaction.TRANSIT_FRAGMENT_CLOSE).replace(R.id.WikiCompany, fragment).commit();
drawer.closeDrawer(GravityCompat.START);
}
}
return true;
}
public void removeAllFragments(){
getSupportFragmentManager().popBackStackImmediate(null,
FragmentManager.POP_BACK_STACK_INCLUSIVE);
}
public void replaceFragment(final Fragment fragment) {
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction().setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN)
.replace(R.id.WikiCompany, fragment).addToBackStack("")
.commit();
}
public void updateDrawerIcon() {
final Handler handler = new Handler();
handler.postDelayed(new Runnable() {
#Override
public void run() {
try {
Log.i("", "BackStackCount: " + getSupportFragmentManager().getBackStackEntryCount());
if (getSupportFragmentManager().getBackStackEntryCount() > 0)
drawerToggle.setDrawerIndicatorEnabled(false);
else
drawerToggle.setDrawerIndicatorEnabled(true);
} catch (Exception ex) {
ex.printStackTrace();
}
}
}, 50);
}
public void resetActionBar()
{
//display home
getSupportActionBar().setDisplayShowHomeEnabled(true);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setHomeButtonEnabled(true);
}
public void setActionBarTitle(String title) {
getSupportActionBar().setTitle(title);
}
}
and In each onViewCreated I call
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
((HomeActivity)getActivity()).updateDrawerIcon();
((HomeActivity) getActivity()).setActionBarTitle("List");
}
This is how I implemented it pre-material design and it seems to still work now I've switched to the new Toolbar. In my case I want to log the user in if they attempt to open the side nav while logged out, (and catch the event so the side nav won't open). In your case you could not return true;.
#Override
public boolean onOptionsItemSelected(MenuItem item) {
if (!isLoggedIn() && item.getItemId() == android.R.id.home) {
login();
return true;
}
return mDrawerToggle.onOptionsItemSelected(item) || super.onOptionsItemSelected(item);
}
I changed the DrawerLayout a bit to get the events and be able to consume and event, such as if you want to use the actionToggle as back if you are in detail view:
public class ListenableDrawerLayout extends DrawerLayout {
private OnToggleButtonClickedListener mOnToggleButtonClickedListener;
private boolean mManualCall;
public ListenableDrawerLayout(Context context) {
super(context);
}
public ListenableDrawerLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
public ListenableDrawerLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
/**
* Sets the listener for the toggle button
*
* #param mOnToggleButtonClickedListener
*/
public void setOnToggleButtonClickedListener(OnToggleButtonClickedListener mOnToggleButtonClickedListener) {
this.mOnToggleButtonClickedListener = mOnToggleButtonClickedListener;
}
/**
* Opens the navigation drawer manually from code<br>
* <b>NOTE: </b>Use this function instead of the normal openDrawer method
*
* #param drawerView
*/
public void openDrawerManual(View drawerView) {
mManualCall = true;
openDrawer(drawerView);
}
/**
* Closes the navigation drawer manually from code<br>
* <b>NOTE: </b>Use this function instead of the normal closeDrawer method
*
* #param drawerView
*/
public void closeDrawerManual(View drawerView) {
mManualCall = true;
closeDrawer(drawerView);
}
#Override
public void openDrawer(View drawerView) {
// Check for listener and for not manual open
if (!mManualCall && mOnToggleButtonClickedListener != null) {
// Notify the listener and behave on its reaction
if (mOnToggleButtonClickedListener.toggleOpenDrawer()) {
return;
}
}
// Manual call done
mManualCall = false;
// Let the drawer layout to its stuff
super.openDrawer(drawerView);
}
#Override
public void closeDrawer(View drawerView) {
// Check for listener and for not manual close
if (!mManualCall && mOnToggleButtonClickedListener != null) {
// Notify the listener and behave on its reaction
if (mOnToggleButtonClickedListener.toggleCloseDrawer()) {
return;
}
}
// Manual call done
mManualCall = false;
// Let the drawer layout to its stuff
super.closeDrawer(drawerView);
}
/**
* Interface for toggle button callbacks
*/
public static interface OnToggleButtonClickedListener {
/**
* The ActionBarDrawerToggle has been pressed in order to open the drawer
*
* #return true if we want to consume the event, false if we want the normal behaviour
*/
public boolean toggleOpenDrawer();
/**
* The ActionBarDrawerToggle has been pressed in order to close the drawer
*
* #return true if we want to consume the event, false if we want the normal behaviour
*/
public boolean toggleCloseDrawer();
}
}
The easiest approach we could do is change the home icon to a known icon and compare drawables (because android.R.id.home icon can differ to different api versions
so set a toolbar as actionbar
SetSupportActionBar(_toolbar);
_toolbar.NavigationIcon = your_known_drawable_here;
for (int i = 0; i < _toolbar.ChildCount; i++)
{
View v = _toolbar.GetChildAt(i);
if (v is ImageButton)
{
ImageButton imageButton = v as ImageButton;
if (imageButton.Drawable.GetConstantState().Equals(_bookMarkIcon.GetConstantState()))
{
//here v is the widget that contains the home icon you can add your click events here
}
}
}
In my case I had to put the icon using:
toolbar.setNavigationIcon(R.drawable.ic_my_home);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayShowHomeEnabled(true);
getSupportActionBar().setHomeButtonEnabled(true);
And then listen to click events with default onOptionsItemSelected and android.R.id.home id
For anyone looking for a Xamarin implementation (since events are done differently in C#), I simply created this NavClickHandler class as follows:
public class NavClickHandler : Java.Lang.Object, View.IOnClickListener
{
private Activity mActivity;
public NavClickHandler(Activity activity)
{
this.mActivity = activity;
}
public void OnClick(View v)
{
DrawerLayout drawer = (DrawerLayout)mActivity.FindViewById(Resource.Id.drawer_layout);
if (drawer.IsDrawerOpen(GravityCompat.Start))
{
drawer.CloseDrawer(GravityCompat.Start);
}
else
{
drawer.OpenDrawer(GravityCompat.Start);
}
}
}
Then, assigned a custom hamburger menu button like this:
SupportActionBar.SetDisplayHomeAsUpEnabled(true);
SupportActionBar.SetDefaultDisplayHomeAsUpEnabled(false);
this.drawerToggle.DrawerIndicatorEnabled = false;
this.drawerToggle.SetHomeAsUpIndicator(Resource.Drawable.MenuButton);
And finally, assigned the drawer menu toggler a ToolbarNavigationClickListener of the class type I created earlier:
this.drawerToggle.ToolbarNavigationClickListener = new NavClickHandler(this);
And then you've got a custom menu button, with click events handled.
Try this code
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if(id == android.R.id.home){
//You can get
}
return super.onOptionsItemSelected(item);
}
Add below code to your onCreate() metod
ActionBar ab = getSupportActionBar();
ab.setDisplayHomeAsUpEnabled(true);
Apart from the answer provided by MrEngineer13, there is also another possible reason why the click event might not have been captured in the onOptionsSelected method. Your DrawerLayout may have overlayed your Toolbar's interface component in the layout XML file. Therefore, whenever you attempt to click the Home button, you're only clicking the DrawerLayout, but not the Home button that's located beneath it.
All you have to do now is rearrange your Toolbar in the corresponding layout XML file so that it is not blocked by any other UI component.
Programmatically, I did attempt to call the bringToFront() method on the toolbar (toolbar.bringToFront()). However, in my app's context, it does not seem to be the solution.